Date of Award


Degree Name

Master of Science


Chemical and Paper Engineering

First Advisor

Dr. R.A. Miner

Second Advisor

Dr. David Peterson

Access Setting

Masters Thesis-Open Access


Mass balances can quantify the dilution and thickening of a liquor/fiber suspension on a brownstock washer. However, the complex displacement process necessitates an empirical approach. Given empirical data, washers can be optimized through use of efficiency factors with mass balances.

Because empirical data is difficult to obtain, a laboratory washing method was developed to empirically generate displacement efficiencies on pulp under mill washer conditions. Reproducible data generated by this method resulted in a displacement/dilution function as seen on mill washers. A laboratory simulation using mill samples, exclusive of problems for one vacuum drum, resulted in comparable efficiencies with less than 10% error.

The relationship between dilution and displacement was examined with a system constant. System constants, which account for the inaccessible dissolved solids portion in the exiting mat, were determined.